One problem related to oil pump has been reported for the 2009 Toyota Highlander. The most recently reported issues are listed below. Please also check out the statistics and reliability analysis of the 2009 Toyota Highlander based on all problems reported for the 2009 Highlander.
2009 Highlander, purchased new, had 105000 miles on 3. 5l v6 engine. Oil changed every 7000 miles, fully synthetic. No warning lights or engine noises prior to incident. Car started after work, drove . 6 mile. Started running very rough, pulled over to shoulder thinking I had a flat tire. Car died before finishing maneuver, coasted to shoulder. Engine would not start. Towed to repair shop, they diagnosed "engine fully seized up". Contacted Toyota, they offered no satisfaction as " car not being repaired by dealer, not under warranty". I find this answer to be wrong, due to low mileage, history of maintenance, no reason for catastrophic failure of engine. Mechanic stated theory of "oil ports clogging up", since heard theory of "oil pump failure".